(Salvation of another) is what man cannot do.  It is impossible. Only God can take out the heart of stone (Eze. 36:26). Only God can draw people to the Son (Jn. 6:44, 65). Only God can open the heart so that it gives heed to the gospel (Ac. 16:14). Only the Good Shepherd knows His sheep by name. He calls them and they follow (Jn. 10:3-4, 14). The sovereign grace of God, doing the humanly impossible, is the great missionary hope.